API stands for Application Programming Interface, which specifies how one component should interact with the other. It consists of a set of routines, protocols and tools for building the software applications.

What is an API Testing?The API Testing is performed for the system, which has a collection of API that ought to be tested. During Testing, a test of following things is looked at.

Exploring boundary conditions and ensuring that the test harness varies parameters of the API calls in ways that verify functionality and expose failures.

Generating more value added parameter combinations to verify the calls with two or more parameters.

Verifying the behaviour of the API which is considering the external environment conditions such as files, peripheral devices, and so forth.

Verifying the Sequence of API calls and check if the API's produce useful results from successive calls.

This course provide API testing coverage by using Following tools

- Functional Testing using Postman

- Pefromance Testing using Jmeter

Types of API testing:

Unit testing - Testing the functionality of individual operations.

Functional testing - Testing the functionality of broader scenarios, often using unit tests as building blocks for end-to-end tests. Includes test case definition, execution, validation, and regression testing.